I wonder if it was be possible to burn DSL to a cd with an extra partition. That extra partition would contain several DSL packages. Main purpose for that is that DSL would still be lightweight and could be ran from RAM, but if user wants to install more programs he/she could find those fast from the other partition. This, ofcourse, wouldn't need internet connection. ;) With this feature DSL could be "as lightweight as before but with heaps of packages".This may be possible also without an extra partition by modifying DSL cd image and adding packages anywhere on the CD image but NOT inside of KNOPPIX image. True?Of corse you can store DSL packages to your USB stick/etc...

Anyway installing packages will eat RAM (as /opt resides in unionfs partition which has the writeable part in tmpfs partition). With older hardware you could just choose not to install more apps. Or... mount a Linux partition from USB stick (or any mass storage device) to /opt. Again, no RAM will be consumed. =)

I don't know how things would be after boot if there are some preinstalled apps in your USB stick (/opt partition). So emptying mounted /opt on reboot/shutdown would be on place. Unless backup.tar.gz contains needed files (for example menu entries for preinstalled programs in /opt).

I don't have the lastest DSL so I don't actually know if there's already features like theese.

That concept has been available since DSL v0.8.0. It is called mkmydsl and allows additional MyDSL extensions on cdrom or dvd without remastering them into the KNOPPIX image. The script has been updated many mnay times view the Notes section and 'find text' mkmydsl.